aculeus

noun acu·le·us \ ə-ˈkyü-lē-əs \

Definition of aculeus

plural aculei \ə-ˈkyü-lē-ˌī\

zoology

: a sharp-pointed process; specifically : an insect's ovipositor especially when modified into a sting

There's more!

Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

More than 250,000 words that aren't in our free dictionary
Expanded definitions, etymologies, and usage notes
Advanced search features
Ad free!

Origin and Etymology of aculeus

borrowed from New Latin, going back to Latin, “stinger, spine (of a fish), sharp point, barb,” from acū-, stem of acus “needle” + -leus, noun suffix (perhaps originally diminutive)

NEW! Time Traveler

First Known Use: 1702

in the meaning defined above

See Words from the same year